Zhi-jun Li

Computer navigation in total hip arthroplasty: A meta-analysis of randomized controlled trials

OBJECTIVE Traditional operation frequently depends on experience of doctors and anatomic landmark visual observation, which often leads to deviation in acetabular prosthesis implantation. Computer navigation technique greatly improves accuracy of prosthesis implantation. The present meta-analysis aimed at assessing the accuracy and clinical significance of computer navigation for acetabular implantation. METHODS All studies published through March 2013 were systematically searched from PubMed, EMBnse, Science Direct, Cechrane library and other databases. Relevant journals or conference proceedings were searched manually. Only randomized controlled trials (RCTs) were included. Two independent reviewers identified and assessed the literature. Mean difference (MD) and Odds ratio (OR) of radiologic and clinical outcomes were pooled throughout the study between navigated and conventional THA. The meta-analysis was conducted by RevMan 5.1 software. RESULTS Thirteen studies were included in the review, with a total sample size of 1071 hips. Statistically significant differences were observed between navigated and conventional groups in the number of acetabular cups implanted beyond the safe zone [OR = 0.13, 95% confidence interval (CI) (0.08-0.22); P < 0.00001], operative time [MD = 19.87 min, 95% CI (14.04-24.35); P < 0.00001] and leg length discrepancy [MD = -4.16 mm, 95% CI (-7.74 to -1.48); P = 0.004]. No significant differences in cup inclination, anteversion, incidence of postoperative dislocation or deep vein thrombosis were found. CONCLUSIONS The present meta-analysis indicated that the use of computer navigation in patients undergoing THA improves the precision of acetabular cup placement by decreasing the number of outliers, and decreases leg length discrepancy. More high quality RCTs are required to further confirm our results.

Safety and efficacy of intra-articular tranexamic acid injection without drainage on blood loss in total knee arthroplasty: A randomized clinical trial

BACKGROUND Major blood loss is unavoidable after primary total knee arthroplasty (TKA). The aim of this study was to determine if tranexamic acid (TXA) can reduce major blood loss following TKA. METHODS In this double-blind, randomized, placebo-control trial, 60 patients treated with unilateral primary cement TKA between August 1st 2013 and September 30th 2013 were randomized into TXA 500 mg intra-articular injection without drainage (test group, 30 knees) and 30 patients with saline intra-articular injection (control group, 30 knees). RESULTS There was a significant reduction in mean blood loss (560.55 mL) between the groups at postoperative day (POD) 5 (999.22 mL vs. 1559.77 mL, P = 0.001). The maximum hemoglobin drop was identified at POD 3 (10.51 g/dL vs. 9.10 g/dL, mean difference = 1.41 g/dL). Also, there was a significant reduction in red blood cell and hematocrit loss (P = 0.001). The transfusion rates (0% vs. 23.3%, P = 0.011) and average amount transfused (0.00 ± 0.00 units vs. 0.53 ± 1.04 units, P = 0.009) were significantly lower in the TXA group compared with control group. No significant difference in coagulation marker changes were found between TXA and control groups (P > 0.05), but the D-dimer levels at 3 and 5 days post-TKA were statistically lower in the TXA group (P < 0.05). No significant changes in the rate of symptomatic deep venous thrombosis, pulmonary embolism, or wound healing problems were noted. CONCLUSIONS TXA treatment without drainage during TKA reduces the amount of blood transfusions required without increasing the rate of adverse events.

Effectiveness of low-level laser on carpal tunnel syndrome: A meta-analysis of previously reported randomized trials.

Background: Low-level laser therapy (LLLT) has been applied in the treatment of carpal tunnel syndrome (CTS) for an extended period of time without definitive consensus on its effectiveness. This meta-analysis was conducted to evaluate the effectiveness of low-level laser in the treatment of mild to moderate CTS using a Cochrane systematic review. Methods: We conducted electronic searches of PubMed (1966–2015.10), Medline (1966–2015.10), Embase (1980–2015.10), and ScienceDirect (1985–2015.10), using the terms “carpal tunnel syndrome” and “laser” according to the Cochrane Collaboration guidelines. Relevant journals or conference proceedings were searched manually to identify studies that might have been missed in the database search. Only randomized clinical trials were included, and the quality assessments were performed according to the Cochrane systematic review method. The data extraction and analyses from the included studies were conducted independently by 2 reviewers. The results were expressed as the mean difference (MD) with 95% confidence intervals (CI) for the continuous outcomes. Results: Seven randomized clinical trials met the inclusion criteria; there were 270 wrists in the laser group and 261 wrists in the control group. High heterogeneity existed when the analysis was conducted. Hand grip (at 12 weeks) was stronger in the LLLT group than in the control group (MD = 2.04; 95% CI: 0.08–3.99; P = 0.04; I 2 = 62%), and there was better improvement in the visual analog scale (VAS) (at 12 weeks) in the LLLT group (MD = 0.97; 95% CI: 0.84–1.11; P < 0.01; I 2 = 0%). The sensory nerve action potential (SNAP) (at 12 weeks) was better in the LLLT group (MD = 1.08; 95% CI: 0.44–1.73; P = 0.001; I 2 = 0%). However, 1 included study was weighted at >95% in the calculation of these 3 parameters. There were no statistically significant differences in the other parameters between the 2 groups. Conclusion: This study revealed that low-level laser improve hand grip, VAS, and SNAP after 3 months of follow-up for mild to moderate CTS. More high-quality studies using the same laser intervention protocol are needed to confirm the effects of low-level laser in the treatment of CTS.

CD47 promotes ovarian cancer progression by inhibiting macrophage phagocytosis

Targeting CD47 efficiently enhances macrophage phagocytosis in both physiological and pathological conditions. Anti-CD47 antibodies have been shown to inhibit the progression of several types of cancer. However, the mechanism of anti-CD47 monoclonal antibody (mAb) treatment remains controversial. In this study, we confirmed that CD47 protein is highly expressed in ovarian cancer, and is correlated with poor clinical characteristics and prognosis. CD47 knockdown in the ovarian cancer cell line, SK-OV-3, promoted phagocytosis by macrophages in vitro and inhibited tumor growth in vivo. These data combined suggest that CD47 inhibition is a potential strategy for cancer treatment. Using an anti-CD47 mAb, we found that CD47 inhibition in both SK-OV-3 cells and primary cancer cells was able to recapitulate our knockdown results and led to an increase in the number of infiltrating macrophages. In addition, the CD133+ tumor initiating cells expressed a high level of CD47, and anti-CD47 mAb treatment was able to trigger the phagocytosis of this cell population. In conclusion, our results indicate that CD47 inhibits macrophage phagocytosis of ovarian cancer cells, and down-regulation of CD47 or inhibiting CD47 by mAb was able to reverse the negative effect. Thus, CD47 antibody therapy may be a promising strategy to treat ovarian cancer.

Reunderstanding of Garden Type I Femoral Neck Fractures by 3-dimensional Reconstruction

Garden type I fractures include incomplete fractures and impacted fractures. With advances in scientific technology and medical treatment, certain deficiencies of the Garden classification have become apparent. The authors hypothesized that the incidence of incomplete femoral neck fractures was low and that impacted femoral neck fractures were not undisplaced and stable fractures. A new method was developed to precisely measure the spatial displacement of the femoral head in impacted femoral neck fractures. Between 2008 and 2011, nine hundred sixty-six patients with femoral neck fractures were treated, 48 of whom had Garden type I fractures, as seen on anteroposterior radiographs. Seven fractures were classified as incomplete on radiographs; however, after 3-dimensional reconstruction, 3 were classified as incomplete and 4 as complete fractures. Furthermore, the remaining 41 Garden I fractures that were classified as impacted on radiographs showed large spatial displacement on 3-dimensional reconstruction. The average rotational displacement of the femoral head was 19.29°±10.51°, and the average displacements of the femoral head center and the lowest point of the fovea capitis were 8.76±4.45 and 14.39±8.08 mm, respectively. This study showed that the incidence of incomplete femoral neck fractures was low. Impacted femoral neck fractures showed variable degrees of displacement and were not undisplaced, stable fractures. Garden classification for impacted femoral neck fractures has certain limitations. Impacted femoral neck fractures should be differentiated from Garden type I fractures so clinicians can select appropriate treatments for these fractures.

Partial versus early full weight bearing after uncemented total hip arthroplasty: a meta-analysis.

BackgroundThis meta-analysis aimed to investigate the efficacy and safety of partial weight bearing (PWB) versus early full weight bearing (FWB) after uncemented total hip arthroplasty (THA).MethodsWe conducted a search in PubMed, EMBASE, The Cochrane Library, and Web of Science for randomized controlled trials (RCTs) and non-RCTs comparing PWB and early FWB after uncemented THA. Two authors conducted the selection of studies, data extraction, and assessment of risk of bias independently. A pooled meta-analysis was performed using the RevMan 5.3 software.ResultsSix RCTs and three non-RCTs met the inclusion criteria. The meta-analysis indicated that compared with PWB, the FWB group showed greater femoral subsidence at 3-month follow-up (MD = −0.12, 95% CI −0.22 to −0.01, P = 0.03). There were no significant differences in the hip Harris score at 1-year and 2-year follow-up (MD = 1.54, 95% CI −0.83 to 3.90, P = 0.20; MD = 0.08, 95% CI −1.19 to 1.34, P = 0.90, respectively), in femoral subsidence at 2-year follow-up and at two additional years of follow-up (MD = −0.03, 95% CI −0.31 to 0.25, P = 0.84; (MD = −0.02, 95% CI −0.37 to 0.33, P = 0.91, respectively). There were no significant differences in the incidences of bone ingrowth fixation, spot welds, and radiolucent lines.ConclusionsThis meta-analysis shows that early FWB in patients with uncemented THA could be safe and could not increase the incidence of postoperative complications.

Postoperative leg position following total knee arthroplasty influences blood loss and range of motion: a meta-analysis of randomized controlled trials

Abstract Aim Postoperative leg position has been reported as an efficient and convenient technique to minimize blood loss and improve early recovery following total knee arthroplasty (TKA); however, no single study was large enough to definitively determine optimal leg position. Therefore, we performed a meta-analysis pooling the results from randomized controlled trials (RCTs) to evaluate the effect of postoperative leg position on blood loss and range of motion (ROM) in TKA. Methods Potential academic articles were identified from the Cochrane Library, Medline (1966–October 2015), PubMed (1966–October 2015), Embase (1980–October 2015), ScienceDirect (1985–October 2015) and other databases. Gray studies were identified from the references of included literature reports. The pooling of data was analyzed by RevMan 5.1. Results Ten RCTs were included in the meta-analysis. There were significant differences in the total blood loss (mean difference [MD] = −130.66, 95% CI: −198.74 to −62.57, P = 0.0002), hidden blood loss (MD = −73.27, 95% CI: −117.57 to −28.96, P = 0.001), blood transfusion requirement (risk difference [RD] = −0.10, 95% CI: −0.19 to −0.22, P = 0.02), postoperative hemoglobin level (MD = 0.73, 95% CI: 0.42 to 1.04, P < 0.00001) and range of motion (MD = 3.79, 95% CI: 1.43 to 6.14, P = 0.002) between the flexion group and extension group. No significant differences were found regarding length of hospital stay, deep vein thrombosis (DVT) and wound infection between the two groups. Conclusions This meta-analysis indicated that the postoperative flexion position of the leg in TKA was effective and safe, significantly decreasing total blood loss, hidden blood loss and blood transfusion requirement. In addition, the postoperative range of motion is significantly improved by the flexion position of the leg.

Biomechanical comparison of mono-segment transpedicular fixation with short-segment fixation for treatment of thoracolumbar fractures: A finite element analysis

Mono-segment transpedicular fixation is a method for the treatment of certain types of thoracolumbar spinal fracture. Finite element models were constructed to evaluate the biomechanics of mono-segment transpedicular fixation of thoracolumbar fracture. Spinal motion (T10–L2) was scanned and used to establish the models. The superior half of the cortical bone of T12 was removed and the superior half of the cancellous bone of the T12 body was assigned the material properties of injured bone to mimic vertebral fracture. Transpedicular fixation of T11 and T12 was performed to produce a mono-segment fixation model; T11 and L1 were fixed to produce a short-segment fixation model. Motion differences between functional units and von Mises stress on the spine and implants were measured under axial compression, anterior bending, extensional bending, lateral bending and axial rotation. We found no significant difference between mono- and short-segment fixations in the motion of any functional unit. Stress on the T10/T11 nucleus pulposus and T10/T11 and L1/L2 annulus fibrosus increased significantly by about 75% on anterior bending, extensional bending and lateral bending. In the fracture model, stress was increased by 24% at the inferior endplate of T10 and by 43% at the superior endplate of L2. All increased stresses were reduced after fixation and lower stress was observed with mono-segment fixation. In summary, the biomechanics of mono-segment pedicle screw instrumentation was similar to that of conventional short-segment fixation. As a minimally invasive treatment, mono-segment fixation would be appropriate for the treatment of selected thoracolumbar spinal fractures.

Safety and Efficacy of Intra-articular Injection of Tranexamic Acid in Total Knee Arthroplasty

Tranexamic acid was intra-articularly injected in total knee arthroplasty (TKA) to reduce blood loss and transfusion. However, no single study has been large enough to definitively determine whether it is safe and effective. To determine the safety and efficacy of intra-articular tranexamic acid in TKA, the authors searched various databases for relevant randomized controlled trials. Mean difference (MD) in total blood loss, risk ratio (RR) for transfusion, and complication rate in the tranexamic acid-treated group vs the placebo group were calculated. Seven randomized controlled trials, including 622 patients (174 men and 448 women), were identified. All 7 placebo-controlled randomized trials had a low risk of bias. The pooled results showed a positive effect of tranexamic acid in all treatment groups, with significant reduction in total blood loss (MD, -396.42 mL [95% confidence interval (CI), -629.64 to -163.20]; P=.0009). However, there was significant heterogeneity in the finding (chi-square=27.16, df=3, I(2)=89%; P<.00001) among studies. The pooled results indicated that 5.8% (18 of 309) of tranexamic acid-treated patients required transfusion compared with 27.2% (85 of 313) of placebo-treated patients. This difference was significant (RR, 0.22; 95% CI, 0.14-0.35; P<.00001). There was no significant difference between the groups in the incidence of deep venous thrombosis (RR, 0.83; 95% CI, 0.35-1.98; P=.68) or pulmonary embolism (RR, 0.54; 95% CI, 0.10-2.85; P=.46). In all, intra-articular tranexamic acid significantly reduced total blood loss, drainage, reduction of hemoglobin, and the need for transfusion without increasing the incidence of deep venous thrombosis and pulmonary embolism. Intra-articular tranexamic acid is safe and efficacious in TKA.

Is PEEK cage better than titanium cage in anterior cervical discectomy and fusion surgery? A meta-analysis

BackgroundThis meta-analysis was performed to identify the benefits and disadvantages of the PEEK cage and titanium cage.MethodsWe used “cervical or cervicle”, “titanium”, and “polyetheretherketone or PEEK” as keywords. Medline, Embase, Cochrane Central Register of Controlled Trials and other databases were searched to identify eligible studies that were published before October 2015. In addition, the Google search engine was used to manually search for relevant journals or conference proceedings. Randomized controlled trials and non-randomized controlled trials that compared the PEEK cage and titanium cage for anterior cervical surgery were included. The meta-analysis was performed with RevMan 5.1 software.ResultsTwo randomized and two non-randomized clinical trials were retrieved with a total of 184 segments from 107 patients in the PEEK cage group and 211 segments from 128 patients in the titanium cage group. The quality assessment scores ranged from 16 to 18 with high heterogeneity. There were no differences in functional status according to the Odom criteria, fusion rate, final local segmental angle and loss of correction between the two groups. Although more subsidence occurred in the titanium cage group, the effects of loss of the local segmental angle or the whole cervical Cobb angle on cervical function in the long-term are still not clear.ConclusionThe present meta-analysis indicated no significant difference in functional and radiographic performance between the PEEK and titanium cages, although more subsidence occurred in the titanium cage group. More high-quality studies are needed to confirm these results to offer more information for the choice in clinical practice.